SU1486770A1 - Two-coordinate angular displacement transducer - Google Patents

Description

The invention relates to measuring equipment. The purpose of the invention is to improve the accuracy of a two-coordinate angular displacement transducer, which contains a hollow split dielectric body 1 with a spherical element 2 disposed therein with a handle 3 for communication with the test object. When you change the position of the object of control (moving the handle 3

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at angles <X or p), the gap between the surface of element 2 and pairs of inductors 5 of an eddy current sensor of gaps, powered by a high frequency voltage and placed in housing 1, changes. Signals on the coils 5 independently of each coordinate are proportional to the angular displacement οί and / 5 respectively. Performing a spherical element 2 with a section 7 of a cylindrical surface in its middle part ensures the creation of a clearly defined dead zone on the output characteristic of the converter in its zero area by selecting the ratio of the sizes of section 7 and the radius of the inductance coils 5, which ensures the accuracy of two-dimensional measurements in terms of vibration noise. 2 Il.

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1486770

The invention relates to a measuring technique and can be used to measure the angular displacements in two coordinates in the systems for controlling the movement of moving objects under vibration conditions.

The aim of the invention is to improve the accuracy of measuring the angular displacements in two coordinates by increasing the linearity of the conversion characteristic outside its deadband.

FIG. 1 shows a two-coordinate angular displacement transducer; in fig. 2 - spherical element of the transducer.

The two-coordinate transducer of angular displacements contains a split dielectric body 1, in the cavity of which a spherical hinge is placed, the spherical element 2 of which is connected to a link with a control object made in the shape of a handle 3. same radius

, as the spherical element 2. The center of the sphere segment of this lining is offset by the value of a relative to the center of rotation of the spherical element of the spherical hinge. In dielectric case 1, an eddy current gap sensor is placed, four identical inductance coils 5 of which are installed in pairs diametrically opposite at equal distances from the center of the segment of the dielectric pad 4. The coil planes are perpendicular to the transverse symmetry planes of the spherical element 2. The outputs of the inductance coils 5 are connected to the measuring electronic unit In the middle part of the spherical element 2 there is a section 7 of a cylindrical surface, the center of which coincides with the center of ment of the dielectric overlay sphere 4, and the axis with the axis of the arm 3. The radius g of section 7 of the cylindrical surface is equal to K _c –K _c , where K. _c is the radius of the inductor, and the height H of this section 7 must be at least three radii K _c inductors. This ensures a greater amount of K _{to the} distance from inductance coils 5 to the surface of section 7 than to the surface of the edge spherical sections of the spherical element 2, Inductance coils 5 are set at the limit of their sensitivity to eddy currents (gap greater than K.) induced in the body spherical movable element 2 of the transducer.

Bicordic angular displacement transducer works as follows.

On the coil 5 inductance voltage is applied to high frequency. In the initial state of the transducer (the angles c7 and p, the rotation of the handle 3 are equal to zero), the gaps between the section 7 of the cylindrical surface of the spherical element 2 and the planes of the inductance coils 5 are equal. As a result, the signals on the inductors are also equal, depending on the electromagnetic fields of the eddy currents flowing in the surface of the cylindrical section 7 of the spherical element 2. As a result, the output signals and and p are zero at the output of the measuring unit 6. The voltage at the output of the measuring unit 6 is close to zero in a certain range of angular displacements <7 and p> of the handle 3, which is determined by the height H of the section 7 of the cylindrical surface corresponding to the required width of the dead zone of the output conversion characteristic. With sufficiently large angular displacements of the arm 3, a significant number of magnetic field lines begins to cross the surfaces of the edge spherical portions of element 2, which are at different distances from the plane of inductance coils 5, but significantly closer than the surface of portion 7. This causes different signals on these coils , as a result, at the outputs of the electronic unit 6, non-zero voltages and C ^ appear, corresponding to the values of the angular displacement <7 and β of the object (not shown) by mutual on perpendicular planes. Since under the coils 5 of the inductance the end sections of the spherical element 2 projecting above section 7 are moved, the characteristic of the converter has a fairly clear deadband boundary. In this case, from the point of view of the influence of the distribution of eddy currents. Coils 5 induk1486770

The potentialities under which the protruding spherical portions of the conductive surface of element 2 move in are approximately in the same conditions.

Phase voltages and can be op- 0 ^ ⁵ Roedel direction angular displacement / p and a control object and use them to control the movement of control elements such as steering devices in the machine control system.

The choice of the height H of the middle section 7, exceeding three radii of the coils 5 of the inductance, eliminates the influence of edge effects on these coils, and the presence of equal-sized protrusions of the extreme spherical areas of element 2 above its middle section 7 is obs. It produces the symmetry of the output characteristic of the conversion at both edges of the deadband of the characteristic By creating such a dead zone, the transducer is insensitive to external destabilizing factors, such as vibrations and accelerations of the test object, transmitted to the transducer movable element through a link with the test object, the handle 3 of the spherical hinge.

Claims (1)

Claim A two-coordinate transducer of angular displacements, containing a detachable dielectric body with a cavity located in this cavity. a hinge, a link for its connection with a controlled object, placed on the surface of a spherical hinge spherical element dielectric pad in the form of a sphere segment of the same radius K _e as the spherical element 'whose center is offset from the center of the latter, eddy current gap sensor, made in the form an electronic unit and four identical inductors connected to it, installed in pairs diametrically opposite in the dielectric case at equal distances from the center of the sphere segment In the middle part of the spherical element, a portion of the surface of rotation of a different radius is made, the center of which coincides with the center of the dielectric overlay segment segment, and the height is at least three inductance coils, in order to increase accuracy by increasing the linearity of the conversion characteristic outside its dead zone, the surface of revolution in the middle part of the spherical element is cylindrical with an axis coinciding with the axis of the link for communication with the object, and a radius equal to K _with -K _to , where K _to - the radius of the inductor.